Burner for fuel-oils.



A. W. THOMPSON.

BURNER FOR FUEL DILs.

APPLIUATION FILED MAR. 10, 1910.

' Patented Aug. 2, 1910.

e 36245, 65 mm unrrnn sTATEs Parana canton. ALBERT W. THOMPSON, 0F MANCHESTER, NEW HAMPSHIRE, ASSIGNOR OF ONE- FOURTH TO HARRY E, BLANGHARI), OF MANCHESTER, NEW HAMPSHIRE.

BURNER non FUnLoILs.

Specification of Letters Patent.

Patented Aug. 2, 1910.

Application filed March 10, 1910. Serial No. 548,344.

T 0 all whom it may concern:

Be it known that I, ALBERT XV. THOMPSON, a citizen of the United States, and resident of Manchester, county of I-Iillsboro, State of New Hampshire, have invented an Improvement in Burners for Fuel-Oils, of which the following description, in connection with the accompanying drawing, a specification, like characters on the drawing representing like parts.

This invention has for its object the production of a simple, novel and ellicient burner for fuel oils, so constructed and arranged that perfect atomization of the oil is etlected without the use of high pressures, either-on the oil or on the air employed to atomize the oil and discharge the same in jet t'orm.

By reason of the low air pressure required I am enabled to use a blower of the rotary fan type for the air supply, instead of cmploying compressed air or steam as an atomizing agent.

The abovc nientioned advantages secured by my novel burner manifestly lead to simplicity of construction and operation and economy of power and fuel.

In the matter of oil pressure I tind in practice that highly satisfactory results are obtained with a pressure of from -1l to 5 pounds per square inch, and with a pressure of from 6 to 8 ounces per square inch for the air.

The various novel features of my invention will be fully described in the subjoined specification and particularly pointed out in the following claims.

Figure 1 is a side elevation and partial longitudinal section of a fuel-oil burner embodying one form of my invention, the Wall of the main air chamber being broken out; Fig. 2 is a transverse section on the line 2-2, Fig. 1, looking toward the left; Fig. 5 is a transverse section on the line 3-.-3, Fig. 1, looking toward the left, but showing the oil-inlet nozzle in elevation.

In the present embodiment of my invention the burner comprises an elongated, tubu lar casing 1, conveniently made as a casting, reduced somewhat in diameter at its open on at 2, and at its opposite closed end 3- having a. suitable gland or stalling box 4, Fig. 1,

for the stem of an oil-controllii'lg valve 5 of any suitable construction. By a nipple 6 the bottom ot the casing is herein shown as connected with a pipe or conduit 7 communicating with a suitable supply of air under low pressure, about from '6 to 8 or 10 ounces per square inch, a suitable air controlling valve or damper 8 being shown in Fig. 1. A transverse diaphragm 9 is formed in the reduced part 2 of the casing, provided with peripheral ports 10, and having on its outer face an annular rib or seat 11, concentric with an elongated tubular extension 12 ex tended centrally from the inner face of said diaphragm, as shown in Fig. 1, and com numicating at its left-hand end with a chantbered portion 13 of the casing and having no communication therewithexceptthrough the said extension. Said chambered portion communicates by a pipe 1 t with a supply of fuel oil at a pressure of about 4 to 5 pounds per square inch, and a suitable valve-seat 15 in the end of the extension 12 cooperates with the valve .5, as clearly shown in Fig.1.

The diaphragm 9 and adjacent p rt of the cxtcusi. '1 are bored and tapped Zlh 16 to receivc the. threaded shank of an oil-inletnozzle 17 which is held fixedly in position bya check-nut 18.

The main interior part of the casing 1 be tween its closed end 3 and the diaphragm 9 constitutes an air chamber 19, Fig. 1 from which the air passes through the ports 10 into the annular passage 20 between the reduced end 2 of the casing and a cylindrical atomizing chamber. For convenience in con struction I make this chamber as a tube 21, reduced in thickness at its outer portion 22 to leave an external annular shoulder 23 and having at its outer end a central outlet 24 of less diameter. The inner, thicker end of the chamber fits tightly intothe annular seat 11 and abuts against the diaphragm as clearly shown in Fi 1, so that said diaphragm forms a clos atomizing chamber, the oil-inlet nozzle 17 communicating axially therewith and projecting thereinto. A retaining ring 25 screwed onto the reduced part 22 of the easing engages the shoulder 23 and holds the atomizingchamber securely in position, said ring having a circularly arranged seriesof inner end for such apertures 26 which communicate with the annular passage 20 surrounding the inner end of the atomizing chamber. The ring is provided With an internally threaded annular flange 27 on its outer face, for a purpose to be described. Near its inner end the atomizing chamber is'provided with one or more substantially tangential inlets 28, shown in dotted lines Fig.2, for the admibsion of air from-the passage 20 to the said Chamber.

Owingto the tangential arrangement of the inlets the air under pressure when admitted to the atomizing chamber assumes a rotary or whirling motiontherein, of relatively high velocity, breaking up or pulverizing and thoroughly a'tomizing the particles of oil admitted through the nozzle 17 and discharging the completely atomized oil from the chamber through its outlet 24. The atomization is thus affected and completed Within the burner, so that the discharge from the atomizing chamber is a jet of perfectly and thoroughly atomized oil, absolutely obviating any dripping. of the burner or the building up of carbonized oil in the interior of the fire-box or furnace.

The air which effects the atomization of the oil is'usually not sufiicient in volume to furnish a proper amount of oxygen for combustion, and the rotative effect upon the issuing jet of atomized oil is so pronounced that such jet tends to expand in conical form with aa'ery Wide'angle of divergence, which is objectionable. I have, accordingly, provided a tapered or conical nozzle 28, Fig. 1, externally threaded at 29 to screw into the flange 27, said nozzle surrounding the outer end of the atomizing chamber concentric therewith, and providing an annular discharge orifice 30 adjacent the outlet 24.

Air from the i'nterior of easing l traverses the passage 20 and passes through the apertures or ports 26 into the nozzle, from which it is discharged through the orifice 30 in the form of an annular jet completely surrounding. the jet ofatomized oil discharged frm the outlet 24L. Such enveloping air j observes the double purpose of concentrating. the jet of atomized oil into a cylindrical, instead of a conical, form, and also provides an. additional amount of fair sufficient to properly support combustion. The completely atomized particles of oil thus move in substantially parallel lines Within and constitute a species of core for the enveloping jet of air. The area of the annular orifice 30 can be varied Within the required limits oi' 'adjustment by rotating the nozzle 28 to move it longitudinally in or out with reference to the threaded flange 27, thereby decreasing or increasing, respec- H tively, the amount of air supplied in the annular enveloping air jet.

From the foregoing description it will be ecaaca apparent that perfect atomization of the oil is effected within the burner itself by or through the action of air at low pressure, the

to get the oil to the .tip of the inlet nozzle l 17, say from at to 5 pounds per square inch. The Oll aperture in said nozzle is relatively large and hence is less likely to cause trouble by clogging than would be the case Witha small outlet aperture, and as the tip of the said nozzle is completely within the burner casing it is not exposed to the heat, and has no tendency to clog from carbonized oil in the tip. Some pressure'on the oil is a prac- V tical necessity, as it permits of regulation of the amount of oil by the valve ,5;,zfth e whirling'or rotary movement in the temizing chamber being requisite to cj riise the separation andbreaking up of the/oil particles in order to eflect atomization and partial distribution. I

In many oil burners the oil is supplied at suflicient pressure to impart avery considerable linear velocity to the jet, and bafiie bricks or tiles are generally relied upon to break up and distribute the flame. With the burner embodying my invention, however, the pressure is only required to cause flow of the oil sutlieient to permit regulation by the valve, the rotary action in the atomizingu chamber being wholly relied upon for atomization, While theair blast provides sufficient linear velocity for proper c istribution. By using low pressure on the oil, with only a single inlet nozzle, a-rela tively large aperture in the nozzle can be used, with consequent diminished tendency to clog.

From an inspection of the drawing it will be manifest that the oil inlet nozzle 17, the outer nozzle 28, the retaining ring 25', and

the atomizing chamber 21, 22 can be readily replaced, any or all of them, in case of breakage or injury, and hence nozzles or atomizing' chambers of Varying capacity or size may be substituted, without in any way,

disturbing the main oil and air connections W1th the burner. By the use of different rings, as 25, having openmgs or ports 26 of varying size, the quantity of air supplied to the outernozzle can be adjustedor varied to suit widely different requirements.

lVhile my burner is primarily designed for low pressures on both oil and air it will be manifest from the foregoing that if desired it can be used for higher pressures and smaller volumes of oil and air. The apparatus is herein described as a burner designed for the atomization of a fuel oil, but the apparatus as described and claimed is equally Well adapted for the atomization of other liquids for various purposes, as will be manifest.

My invention is not restricted to the precise construction and arrangement herein shown and described, as the same may be modified or rearranged in various details by those skilled in the art without departing from the spirit and scope of my invention as set forth in the-claims annexed hereto. 4

Having fully described my invention, what I claim as new and desire to secure by Letters Patent is 1. In an oil burner, an atomizing chamber provided with a tangential inlet for the admission of air under ressure, and an axial outlet at one end 0 the chamber, an inlet member for oil under pressure, communicating axially with said chamber at its other end, and means to provide an annular jet of air concentric with and adjacent the outlet of the atomizing chamber.

2. In an oil burner, an atomizing chamber provided with a tangential inlet for the admission of air under pressure, and an outlet at one end, means to introduce oil under pressure to said chamber at its opposite end, and adjustable means to surround the jet of atomized oil discharged from the chamber with a jet of air adjacent the chamber outlet.

3. The combination with an atomizing chamber having an unobstructed outlet at one end and closed at its opposite end, and means to introduce air at low pressure to said chamber between its ends and efiect rotary motion of the air within the chamber, of an inlet nozzle for a liquid under pressure, communicating axially with the closed end of said chamber opposite its outlet, the rotating air in the chamber atomizing the liquidintroduce'd thereinto, and means concentrically surrounding the outlet of said chamber to surround the jet of atomized liquid discharged from the chamber with an annular, non-rotatable jet of air.

4. The combination with an atomizing chamber having at one end an axial inlet communicating with a supply of liquid under pressure,--and an outlet at its opposite end, of means toiiitroduce air at low pressure into said chamber and effect rotary motion of the air Within the chamber, and an adjustable tubular nozzle concentrically surrounding said chamber and having its outlet adjacent theoutletof the chamber, to discharge a non-rotatable and annular jet of air at the outlet of said chamber and concentric with such outlet.

In an oil burner, a casing communicating with a supply of air under pressure and having a circularly arranged series of outlets at one end, a circular chamber within the casing and surrounded by said outlets, a tangential inlet for the admission of air from the casin means to introduce oil under said chamber at the inner end. t ereof, and, a tapered nozzle at the outlet end of the casing concentric with the chamber, to deliver;

an annular jet of air surrounding the atomized oil discharged from the outlet of the chamber.

6. In an oil burner, an air chamber having a tubular outlet and communicating with a supp-ly of air under pressure, a circular atomizing chamber supported within the air chamber and extended into the tubular outlet thereof, said atomizing chamber having an axial outlet at its outer end and a tangential inlet communicating with the air chamber, and an inlet for oil communicating axially with said atoinizing chamber at its inner end.

7. In an oil burner, an elongated cylindrical chamber having an axial outlet at one end and a tangential inlet for the admission of air under pressure, an oil-inlet nozzle communicating with a sup ly of oil under pressure and extended axia ly into the end of said chamber opposite itsoutlet, and a conical, longitudinally adjustable nozzle concentric with said chamber and surround ing its outlet end, said nozzle communicat-' ing with the air supply.

8. In an oil burner, a tubular casing open at one end and adapted to be connected with an air supply at low pressure, a transverse diaphragm Within the casing near its open end, having peripheral ports, and an annular seat on its outer face, an oil-inlet nozzle extended through the diaphragm at the center of the seat and communicating with a supply of oil, a tubular atomizing chamber supported at its inner end in said seat and closed thereat by the diaphragm, the oil-inlet nozzle extending axially into the chamber, the latter having an outlet at its outer end and a tangential inletrommunicating with the casing, for the admission of air therefrom to the chamber, a perforated reto said chamber, and axial outlet 1n tlie outer end of the chamber,

ressure into i taining ring on the open end of the casing,

and surrounding the outlet end of tl1e,atoniizing chamber. a 9. In an oil burner, an elongated cylindrical chamber closed at one end and having a central outlet at its other end, andwprovided near its closed end with a tangential inlet for the admission of air under pres sure, a nozzle for the admission of oil under pressure, extended axially into said chamber at its closed end, and manually adjustable means to discharge an annular jet of air at and surrounding the outlet of said chamber.

10. In an oil burner, an atomizing chamber having a central outlet and communicatthe chamber, to break up and'aqomize the parti "es. w? oil admitted thereto and discharge the atomized oil through the central outlet of the chamber, and means to discharge an annular jet of air' at such outlet,

" seems to surround and concentrate the jet of atom- 10 ized oil.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribin Witnesses.

AEBER T W. THOMPSON.

Witnesses:

I'IIRAM A. STEARNS, EARRY En Lovmzmw. 

